Forge actuator spring advice please?

[officerbrooks]

Hi all,
I have a 2001 ME7 C70 T5, 16T with RICA map 3" downpipe ferrita cat and exhaust. I suspect the actuator is a little tired at 120,000 mls as with everything else checked and replaced boost isn't holding.
What should be my starting point with the following actuator spring choices and will it be the ME7 software and map that actually overides the quoted "running pressure"?

Thanks.

T2 actuator spring selection guide from Forge Motorsport.



The following is general information regarding Forge actuator spring tensions and are important considerations when making a decision on which spring you install, especially if you are running a boost controller or planning an ECU upgrade.

The 4 springs we offer are listed below under their relevant colour codes and related pressures. Running pressure is the lowest or minimum pressure the spring will operate at, which is important when considering which spring you choose. The spool up pressure relates to the vacuum pressure required to lift the spring from its static position, at which point the turbo waste-gate will start to open (spool up).

The actual rating for these springs is as follows, the lower pressure being the spool up pressure and the higher pressure being the running pressure:

RED 17 psi (spool up) - 20 psi (running pressure) our product code FMAS049R.

BLUE 14 psi (spool up) - 18 psi (running pressure) our product code FMAS049B.

YELLOW 9 psi (spool up) - 15 psi (running pressure) our product code FMAS049Y.

GREEN 5 psi (spool up) - 10 psi (running pressure) our product code FMAS049G.

The spool up can be altered to a higher pressure by adding more tension to the spring. Be careful not to add too much tension to the spring as it will become coil bound, affecting the rod travel and thus affect the waste-gates ability to open effectively. Running pressure cannot be adjusted by adding pressure to the spring.
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[M-R-P]

Standard running pressure is about 10psi so I would think, with the remap, probably the blue or possibly the red (the red may be too much tho)

[Wobbly Dave]

I wouldn't use a forge anything as far as I could throw it. If indeed your current actuator is getting on a bit - just replace it with a genuine one or depending on how much slack there is in the rod you can tighten it up 1/2 turn or even 1 full turn.

Because it is ME7, & on demand you just need to tweek it a little to get yourself back in the game. That's how I got from 14.5 to 13.9 on the quarter with Betsy.

How have you arrived at the conclusion that it is infact your actuator which is at fault? Boost may not hold for any number of reasons. ME7 is after all on demand.

[officerbrooks]

I wouldn't use a forge anything as far as I could throw it. If indeed your current actuator is getting on a bit - just replace it with a genuine one or depending on how much slack there is in the rod you can tighten it up 1/2 turn or even 1 full turn.

Because it is ME7, & on demand you just need to tweek it a little to get yourself back in the game. That's how I got from 14.5 to 13.9 on the quarter with Betsy.

How have you arrived at the conclusion that it is infact your actuator which is at fault? Boost may not hold for any number of reasons. ME7 is after all on demand.

Thanks, my self diagnosis follows after watching my Stax boost guage show 1.45bar then drop to 1.2 then hold at 1 bar on WOT, I thought it should hold higher boost until max rpm. All pipework is new and secure including the TCV and it has a Snabb intake pipe.

[M-R-P]

The 16t runs out of puff at high revs, could go some way towards explaining it..?

[p fandango]

Standard running pressure is about 10psi so I would think, with the remap, probably the blue or possibly the red (the red may be too much tho)

yes they do run 10psi standard, but that because the ECU raises the pressure via the BCS. Standard actuator pressure is very low, about 4-5psi i believe

[M-R-P]

That's always confused me - the bcs takes a feed directly from the compressor and either goes to the actuator or back to the inlet. How does the pressure get halved?

[officerbrooks]

This is all helpful info I did have more top end performance but feel its dropped off leading me to fit the boost guage to monitor. I'm looking for a larger drop in intercooler too as I suspect high AIT's play a large part in this. All advice on any of this topic is extremely welcome, thanks.

[Wobbly Dave]

If you are close to me I can test with the TORQUE app & get a full picture & data log your AITs. I would be very dubious that the ME7 RICA map would allow 1.45. It certainly will not push & hold that within that RICA map. Boost gauge is questionable.

[T5frankie]

boost tailing of as you climb the revs is normal and all cars do it

[Jamest5r]

boost tailing of as you climb the revs is normal and all cars do it

Mine dont

[Jamest5r]

yes they do run 10psi standard, but that because the ECU raises the pressure via the BCS. Standard actuator pressure is very low, about 4-5psi i believe

Yep thats right.

That's always confused me - the bcs takes a feed directly from the compressor and either goes to the actuator or back to the inlet. How does the pressure get halved?

Little hole in the BCS

[ROZER]

Thanks, my self diagnosis follows after watching my Stax boost guage show 1.45bar then drop to 1.2 then hold at 1 bar on WOT, I thought it should hold higher boost until max rpm. All pipework is new and secure including the TCV and it has a Snabb intake pipe.

i have a s60 t5 with all the same mods as you and mine boosts just like yours but holds 18psi.

[T5frankie]

Mine dont

ill enjoy beating you on sunday

[officerbrooks]

If you are close to me I can test with the TORQUE app & get a full picture & data log your AITs. I would be very dubious that the ME7 RICA map would allow 1.45. It certainly will not push & hold that within that RICA map. Boost gauge is questionable.

Thanks, think I'm a long way from you in Windsor. I get 1.45bar immediately as a peak it then settles and holds 1.2bar dropping then to 1 bar by 5-5.5krpm. Maybe this is normal for a car of my spec but it did have a little more, guess I'm at the limit of my current hardware.

[960kg]

The basic setting pressure of the actuator is 4.35psi for the B5234T3 but this is done with compressed air on the actuator diaphragm and not from the turbo when the engine is running so the operating psi is not halved at all as it has no real reference to the turbo pressures.

In my experience the 16T does not run out of puff at high revs and most standard cars don`t either, as the turbo fitted is within it`s efficiency range, hence different turbo`s on different models to suit.

It depends what exhaust you have fitted as the turbo pressure drops when a larger diameter exhaust or down pipe what ever is fitted, so then you turn up the boost to compensate and then you have not much boost left at higher revs. because you have surpassed the turbo`s efficiency that you have fitted.

I studied and read what i could find as i was getting a new exhaust and did not know what to fit and at the moment with a standard exhaust and very modified standard airbox and remap i am getting 20psi at the rev limiter.

So for me at the moment i like the boost at higher revs. i will keep the exhaust on hold until it falls off then decide what to fit, of course if the actuator has too many turns the turbo spools earlier as well so will run out earlier, but to state it does this or that all depends on your setup.

As far as Forge Actuator is concerned, ok i think they do a service as the pucker Volvo one ordered from Sweden only is £207 including VAT.

I have fitted the Forge Recirculating Valve but to be honest it`s noisy as it is a piston type and upon removal of the standard diaphragm type it was in excellent condition even after 159,0000
so really for me was a waste of effort and money. My `98 T4 held 20psi for two years and was still ok on the standard valve.

Everyone to there own.

[dtp]

I have the red spring in mine. My map is asking for 1.4bar boost. Until I changed my actuator my boost hit a peak of 1.4 then almost immediately dropped to 1.2bar then after 5,500 dropped to 1.1. I fitted a forge actuator pressured the diaphragm to 0.4bar and turned adjuster to just touch the arm. Now if I floor it I get 1.5bar peak this drops down to 1.4 bar and holds till the red line. I can only put this down to the OEM actuator being very tired and I was getting waste gate creep.

[claymore]

Mine dont

Nore mine

[Redbrick]

Black FTMFW :

[officerbrooks]

I have the red spring in mine. My map is asking for 1.4bar boost. Until I changed my actuator my boost hit a peak of 1.4 then almost immediately dropped to 1.2bar then after 5,500 dropped to 1.1. I fitted a forge actuator pressured the diaphragm to 0.4bar and turned adjuster to just touch the arm. Now if I floor it I get 1.5bar peak this drops down to 1.4 bar and holds till the red line. I can only put this down to the OEM actuator being very tired and I was getting waste gate creep.

Thanks, may I ask at what rpm your boost develops with that spring and on my car would the boost control be via the ME7 and RICA regardless of the spring type? You can tell this is a steep learning curve for me!